Last updated: April 23, 2026
Furnace repair in San Diego County typically runs $200 to $900, starting with an $89 diagnostic that gets credited toward the fix. Ignitor and flame sensor problems make up most of the cheap end. A cracked heat exchanger is the one repair that usually means it's time to talk about replacement instead.
San Ysidro's housing stock is mostly older 1940s-70s residential with heavy multi-family rental inventory near the Port of Entry, which keeps typical project scope smaller than in the newer master-plan communities further north. Mini-split retrofits are common where central ducting was never installed. Permits route through the City of San Diego. Mid-range inland heat, 90 to 100 degrees common, is less severe here than El Cajon or Santee but still real.
South Bay heating demand is modest, so furnace repair volume is lower here than inland, and most calls are routine ignition or thermostat-wiring issues priced at the county baseline. Gas furnaces and heat pump heating repair the same way here; we don't price one differently.
| Item | Typical cost | Notes |
|---|---|---|
| $89 diagnostic visit | $89 | Credited toward the repair once you approve the work |
| Hot-surface ignitor replacement | $250 - $500 | The most common reason a furnace won’t light |
| Flame sensor cleaning or replacement | $150 - $350 | Causes the furnace to shut off seconds after igniting |
| Inducer motor replacement | $400 - $800 | Furnace hums or clicks but won’t start the burner cycle |
| Gas valve replacement | $400 - $900 | Safety component, always tested before replacement is approved |
| Control board replacement | $400 - $800 | More common on furnaces with electronic ignition and diagnostics |
| Blower motor replacement | $450 - $900 | Furnace heats but airflow through the vents is weak or silent |
| Heat exchanger replacement | $1,500 - $3,500 | A safety-critical repair, often the point to consider a new furnace instead |
Ranges reflect San Ysidro and South County San Diego. Your exact figure depends on the factors below. We quote flat-rate before starting.
A furnace repair under roughly $500 on a unit less than 12 years old is almost always the right call. A cracked heat exchanger is different. It's a safety issue, not just a repair line item, because a cracked exchanger can leak combustion gases into the home. On a furnace old enough to need one, we usually recommend replacement over repair, and we explain exactly why before you spend money either way.
The $89 diagnostic gets credited toward the repair once you approve it. SDG&E and TECH Clean California rebates apply to new equipment, not repairs, so they come into play only if a repair turns into a replacement conversation, most often after a heat exchanger fails. We offer financing for larger repairs, and we'll tell you plainly when a repair isn't worth it anymore.
For most of San Ysidro's older multi-family stock, yes, mostly because there's rarely existing central ductwork to reuse. A single-zone ductless heat pump for one rental unit typically runs $4,500 to $8,000 installed, well under what retrofitting central ducting into an older building would cost, and it handles both heating and cooling from one compact outdoor unit.
South Bay heating demand is modest, so furnace repair volume is lower here than inland, and most calls are routine ignition or thermostat-wiring issues priced at the county baseline. Gas furnaces and heat pump heating repair the same way here; we don't price one differently.
$200 to $900 covers most repairs, including the $89 diagnostic that gets credited toward the fix. Ignitor and flame sensor issues run under $500. A gas valve, control board, or blower motor runs $400 to $900.
Usually yes if the repair is under $500 and the furnace is less than 12 years old. A cracked heat exchanger is the exception. That's a safety issue, and on an older furnace we typically recommend replacement instead.
A flame sensor cleaning or replacement is usually the least expensive fix, typically $150 to $350, and it's one of the most common reasons a furnace shuts off right after lighting.
A heat exchanger replacement runs $1,500 to $3,500 and is the most expensive single repair. Because of the safety issue involved and the age of furnaces that usually need one, we walk through the full replacement cost alongside it.
Flat-rate pricing, confirmed before any work starts. Same-day scheduling on most calls.